However as far as I understand it, you can only be refunded the amount that you paid. My fiance had around 6000 in education tax credits, however she only paid around 500 in taxes, so she only got 500 back from the Feds. It is either bad math, or bad English to get a refund greater than the amount paid.
I assure you, you can get back more then you paid. The wife and I paid in roughly $4000 this year(about $500 more then we 'owe'), and we got back over $6000. I don't know how education tax credits work. I do know that for each kid you have, the feds give you $1000, no matter what you've paid in.